The recent increase in the average age of the population has been accompanied by an increase in circulatory diseases, such as hypertension, angina and myocardial infarction. In particular, there have been many sudden occurrences of acute myocardial infarction with a high mortality rate. Hitherto, the cause of this acute myocardial infarction has been attributed to obstruction, by thrombus or coronary spasm, of the coronary antery which supplies nutrition to the heart. Recently, however, Kaneko et al. have proposed a new mechanism for acute myocardial infarction, according to which the myocardia of myocardial infarction patients exhibit two forms of necrosis, Static cell death (SD) and Kinetic cell death (KD), with KD being the main cause of acute myocardial infarction. (Journal of Tokyo Women's Medical College, 52, 1443, 1982). In addition, Kaneko et al. have reported using a rabbit to create a model of an acute myocardial infarction caused by KD, and using calcium antagonists to inhibit the symptoms thereof (refer to Japanese Patent Application No. Sho 61-40651). Moreover, they have recently succeeded in creating a model of an acute myocardial infarction caused by KD in a Langendorff in vitro system using an isolated rat heart, and using this model they have found that some Ca antagonists have a KD-inhibiting effect similar to that found in the in vivo system. However, some of these Ca antagonists have a strong cardiodepressant effect, and it was thought desirable to develop compounds having a weak cardiodepressant effect, and a strong KD-inhibiting effect.